See also:

Fuel-Filler Lid and Cap
WARNING: When removing the fuel cap, loosen the cap slightly and wait for any hissing to stop. Then remove it: Fuel spray is dangerous. Fuel can burn skin and eyes and cause illness if ingested. ...

Engine Compartment Overview
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Accessory Sockets
The ignition switch must be in the ACC or ON position to prevent the battery from discharging. Only use genuine Mazda accessories or the equivalent requiring no greater than 120 W (DC 12 V, 7 A ...